Background and Purpose:Children with acute myeloid leukemia and relapses of leukemia are at high risk of developing fungal infections and need antifungal prophylaxis. This study aimed to compare the efficacy and toxicity of two different dosage regimens of voriconazole (VRCZ) during prophylactic administration in children with malignancyand neutropenia. Materials and Methods:This prospective study was conducted at the Belarusian Research Center for Pediatric Oncology, Hematology, and Immunology fromMay 2017 to December 2019. The present study included 21 Caucasian patients with malignant hematological diseases (20 patients with acute myeloid leukemia and relapses of leukemia and 1 patient with Non-Hodgkin's lymphoma) aged 2-18 years. All patients were randomly divided into two groups that received different dosage regimens of VRCZ prophylaxis. Patients in the “high-dose” group received VRCZat a dose of 9 mg/kg twice a day PO, or 8 mg/kg twice a day IV without a loading dose (children of 2-11 and adolescents and of 12-14 years old with. Results:In the high-dosegroup (n=20 episodes of prophylaxis), invasive fungal infections (IFI) signs were recorded in one (5%) case. In the low-dose group (n=20 episodes), IFI signs were observed in six (30%) cases (P=0.0375). The residual serum concentration was significantly higher in patients who received high doses of VRCZ (p <0.0001). Most patients with IFI (n=6, 86%) had a mean value (i.e.,) Conclusion:The likelihood of IFI was significantly lower in children who prophylactically received VRCZ in high doses (P=0.0375) and had ≥ 0.74 μg/ml residual serum concentration of the medication (P=0.0258). Residual serum concentration of VRCZ reached a plateau by day sixth of the treatment. In children, the dosage was the only highly significant factor affecting the metabolism of VRCZ.

Background and purpose: Patients with hematological malignancies are at risk of fungal infections and require quick diagnostics infection complications. The following study aimed to evaluate the effectiveness and relevance of the use of biomarkers of procalcitonin (PCT), C-reactive protein (CRP), galactomannan (GM), and bis (methylthio) gliotoxin (BMGT) in the diagnosis of fungal infections in patients with oncological and hematological diseases. Materials and methods:The prospective study was conducted at the Belarusian Research Center for Pediatric Oncology, Hematology, and Immunology from April 2015 to January 2020. The study included 66 children with malignant hematological diseases aged 1 to 17 years. Clinical, microbiological, and statistical methods were used in the study. Results:In the case of fungemia in children with oncological and hematological diseases, the PCT level during the infectious episode was significantly lower than with bacterial infections of the bloodstream (p = 0.0063); and the СРR level in cases of fungal and bacterial infections did not differ significantly (p = 0.1719). Diagnostic study of GM in bronchoalveolar lavage had a high predictive value of a negative result (91.7%). The method's sensitivity was higher than in the study of GM in serum (50% versus 0%). There was no correlation between serum BMGT levels as measured by HPLC and the presence of invasive aspergillosis in children. Conclusion:An increase in СRP levels with normal PCT levels in immunocompromised children with clinical signs of bloodstream infection is indicative of a fungal etiology of the disease. Determination of the optical density index of galactomannan in the bronchoalveolar fluid is a sensitive marker for diagnosing invasive pulmonary aspergillosis in children. We cannot recommend BMGT for the diagnostics of invasive aspergillosis in children.